Try manually resetting all your plugins (no Dashboard access required) and see if that let’s you regain access.
It appears that the real issue is that your domain registration has expired.
whois pevenseybaybaptist.org.uk
[Querying whois.nic.uk]
[whois.nic.uk]
Domain name:
pevenseybaybaptist.org.uk
Data validation:
Nominet was able to match the registrant's name and address against a 3rd party data source on 04-Sep-2014
Registrar:
SME IT Solutions Limited [Tag = SMEITSOLUTIONS]
URL: http://www.smewebsolutions.co.uk
Relevant dates:
Registered on: 04-Sep-2014
Expiry date: 04-Sep-2018
Last updated: 05-Jul-2018
Registration status:
Renewal required.
*** This registration has been SUSPENDED. ***
You need to fix that with your domain registrar.